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S Beppu

Publications and source records attributed to S Beppu.

At least 91 records · Page 5Linked to original sources
PubMed1987

[Effect of brain death on hemodynamics and cardiac function: an experimental study].

An experimental model was designed to study hemodynamic and left ventricular functional changes in the course of and after brain death in 13 mongrel dogs. Brain death was induced by creating intracranial hypertension by inflating a balloon inserted into the subdural space. Hemodynamic parameters and left ventricular systolic function as assessed by echocardiography were measured before and during intracranial hypertension and 30 min and 1, 2, 3, 5 and 8 hrs after brain death. During intracranial hypertension, heart rate, systemic and pulmonary blood pressures, cardiac output and systemic vascular resistance raised significantly. After brain death, all parameters decreased rapidly and significantly, and then stabilized. On comparison with values obtained before intracranial hypertension, systemic blood pressure decreased markedly following brain death, while no marked change was noted in cardiac output. This result is attributable to a marked reduction in peripheral vascular resistance following the induction of intracranial hypertension. The left ventricular end-diastolic and end-systolic diameters did not change; consequently, fractional shortening did not change, either. The Weissler's index improved after brain death, reflecting a marked reduction in systemic vascular resistance. This indicates limited usefulness of afterload-dependent cardiac indices. At the agonal period of brain death, three of 13 dogs died because of ventricular fibrillation or a marked decline in systemic blood pressure. Within five to eight hours after brain death, seven dogs died because of intractable acidosis. These results represent the specific hemodynamic features occurring after brain death. It is thought that recognition of these features is useful in managing cases of brain death and in selecting donors for heart transplants.

Animals↗
PubMed1986

Jugular phlebogram in congenital absence of the pericardium.

The purpose of this study was to emphasize the diagnostic value of the jugular phlebogram in congenital absence of the pericardium. Phonocardiographic study was performed in seven patients with complete absence of the left pericardium and in four with partial pericardial defect (left sided in three, right sided in one). Associated heart lesions were absent in all patients. The characteristic features of the jugular phlebogram in these patients were decreased depth of x descent and tall v wave followed by deep y descent (M-shaped pattern). These jugular abnormalities were more prominent in complete absence of the left pericardium than in partial pericardial defect. The x descent was completely obliterated in two patients with complete left pericardial defect. Loss of decrease in pericardial pressure during ventricular ejection and altered cardiac position as a result of the absence of the pericardium may be responsible for these jugular abnormalities. Jugular venous M-shaped pattern may be one of the useful physical and phonocardiographic indicators for the diagnosis of congenital absence of the pericardium.

Adolescent↗
PubMed1986

Primary failure of Hancock porcine bioprosthetic valves: two dimensional echocardiographic assessment.

To reveal the process of primary failure of the Hancock porcine bioprosthetic heart valve, a real-time two-dimensional echocardiography was undertaken. There were 75 cases (84 valves) with 26 in the aortic valve position, 39 in the mitral valve position, 9 in both the aortic and mitral valve positions, and 1 in the tricuspid valve position. The subjects comprised 35 males and 40 females, whose ages ranged from 18 to 65 years with a mean of 44.7 years. Valvular changes such as thickened valve cusps or abnormal valve movement were observed in 27 (32%) of the 84 valves; more specifically, in 5 (14.3%) of the 35 aortic valves and in 22 (45.8%) of the 48 mitral valves, indicating that valvular changes occurred most frequently in the mitral valve position (p less than 0.01). In the period between valve replacement surgery and the appearance of valvular changes, no significant difference was noted between aortic and mitral valve bioprostheses. The duration ranged from 14.5 to 74.5 months with a mean of 50.2 months. Valvular changes were evident in more than 50% of the valve bioprostheses implanted 6 or more years ago. In the mitral valve position, valve cusp changes appeared more frequently at the anterior cusp than at the inner and outer cusps. The frequency was 17 cases at the anterior cusp, 6 at the inner and 9 at the outer. In 7 of the 11 cases followed up after the appearance of valvular changes, an increase in the changes was recognized 7.5 to 29.5 months (a mean of 16.4 months) later.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1986

[Postural effects in the jugular phlebogram in patients with complete absence of the left pericardium].

To elucidate the function of the pericardium, alterations in jugular phlebograms, intracardiac pressures and cardiac volumes induced by postural changes were examined in seven patients with complete absence of the left pericardium. Ten patients with ischemic heart disease were studied as controls. Jugular phlebograms in patients with complete absence of the left pericardium showed decreased depths of the x descent and the tall v waves followed by the deep y descents (M-shaped pattern) in the supine position. These jugular abnormalities were exaggerated in the left lateral decubitus position. By contrast, the jugular phlebograms tended to return to normal, but remained abnormal in the right lateral decubitus position. Right atrial pressure curves showed similar postural effects. However, the jugular phlebograms and right atrial pressure curves in patients with ischemic heart disease were not altered by postural changes. The characteristic alterations of the jugular phlebograms are useful indicators for diagnosing complete absence of the left pericardium. The lack of a prompt decrease in pericardial pressure during ventricular ejection due to the absence of the pericardium is one of the causes of a decreased depth of the x descent in pericardial defect. However, this cannot explain the postural alteration of the jugular phlebogram. Another possible mechanism is the decreased excursion of the tricuspid ring during systole. As indicated in our previous report, there is anterior movement of the cardiac apex during systole in cases of pericardial defect, which is exaggerated in the left lateral decubitus position and decreased in the right lateral decubitus position due to the lack of normal pericardial support. This anterior swinging motion may inhibit the descent of the tricuspid ring toward the apex, resulting in a decreased depth of the x descent of the jugular phlebogram and the right atrial pressure curve and their postural alterations. The right ventricular volume as calculated from cardiac computerized tomography and the right ventricular end-diastolic pressure were not altered significantly by postural changes in the control cases. These indices increased to a greater extent in the left lateral decubitus position than in other postures in cases with pericardial defects.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1986

[Pericardial defect: roles of the pericardium on kinetoanatomic changes of the heart influenced by patients' postures].

To elucidate the physioanatomic roles of the pericardium, the alterations in gross anatomy and cardiac motion induced by posture were examined by two-dimensional echocardiography in seven patients with total absence of the left pericardium. Ten healthy subjects were served as controls. The heart was located deeper within the chest at end-diastole in patients with pericardial defect than in healthy subjects, especially in the left lateral decubitus position. With progression of systole, the cardiac apex swung anteriorly with the cardiac base as the fulcrum, and the heart approximated the normal position at end-systole. The deeper the position of the center of the cross-section of the left ventricular cavity at end-diastole, the more exaggerated the swinging motion in systole. The deep location of the heart in end-diastole is considered to result from release from pericardial support, and the systolic tonus of the cardiac muscle restores the apex to nearly normal position. The characteristic swinging motion of the heart and its alterations dependent of posture seemed the signs suggestive of total absence of the pericardium. The shape of the short-axis view of the left ventricular cavity was nearly circular throughout the cardiac cycle. Therefore, paradoxical motion of the ventricular septum observed on M-mode echocardiography in pericardial defect results from the anterior shift of the entire heart overcoming the proper motion of the interventricular septum. The left ventricular dimension become enlarged according to the postural change from the right to left lateral decubitus positions regardless of the presence or absence of the pericardium. The right ventricular cavity became enlarged in the left lateral decubitus position in patients with pericardial defect. The elevation of hydrostatic pressure due to postural change was considered excessive due to the absence of the pericardium. In the left lateral decubitus position, systolic excursions of the mitral and tricuspid rings became more prominent in healthy subjects, whereas these excursions, particularly of the tricuspid ring, were reduced in patients with pericardial defect. Depressed tricuspid ring motion was also observed in the right lateral position in cases with pericardial defects. The reduced excursion of the tricuspid, ring and the right ventricular dilatation may affect systemic venous return to the right atrium.

Adult↗
PubMed1985

Smoke-like echo in the left atrial cavity in mitral valve disease: its features and significance.

In some patients with mitral stenosis, a smoke-like echo is observed in the left atrial cavity. The present study in 116 consecutive patients with rheumatic mitral valve disease investigated the echocardiographic features and clinical significance of this echo. The smoke-like echo is characterized by the following echocardiographic features: 1) it is composed of numerous microechoes; 2) it curls up slowly in the enlarged left atrial cavity; and 3) it vanishes as soon as it pours into the ventricular cavity. Hemostasis in the left atrial cavity was considered to be an important underlying condition for development of the echo. Hemorheologic conditions indicated that the shear rate of blood flow in the left atrial cavity was calculated to be low enough for the development of red blood cell aggregation. These conditions suggest that the source of the smoke-like echo might be aggregated cells due to hemostasis in the left atrial cavity. Left atrial thrombi were detected in many patients who had this echo in the left atrial cavity. Although it has not been conclusively determined that the presence of the smoke-like echo is a necessary condition for thrombus formation, this echo appears to be closely related to thrombus formation in the left atrial cavity. It is concluded that the presence of this echo indicates severe left atrial hemostasis and is a warning for thrombus formation.

Adult↗
PubMed1985

[Two-dimensional echocardiography in diagnosing the region of myocardial infarction: a comparative study by several independent examiners].

The efficacy of two-dimensional echocardiography in diagnosing the localization of myocardial infarction (MI) was studied by comparing the echocardiographic and pathological findings of 28 patients having MI. The ventricular wall was divided into 18 segments including three segments of the right ventricular wall. The regional wall motion abnormalities for each of the 504 segments were diagnosed by visual assessment. The echocardiographic recordings were reviewed individually by four examiners using the same protocol to assess the interobserver's variation. The receiver operating characteristics (ROC) curves differed by examiners. However, when the subjects were limited to anterior MI patients, the ROC curves established by the echo-trained physicians did not differ significantly. It was concluded that the echocardiographic diagnosis of regional wall motion by visual assessment has universal validity. Individual differences are thought mainly to depend on the sites of infarction. Sensitivities for detecting transmural (TM), non-transmural (non-TM) infarcted segments and intact segments were 90, 70 and 70%, respectively. Most of the underestimated TM or overestimated intact segments corresponded to the sites adjacent to MI. As the unexpectedly misdiagnosed segments, the mimic inward motion of the inferior wall drawn by the intact anteroapical wall was observed in a inferior MI patient, or the mimic anterior motion of the anteroapical wall by a swinging motion of the heart, or the paradoxical motion of the interventricular septum was observed in a right ventricular MI case. In the two third of the overestimated non-TM segments, it was considered that the wall motion was affected by the myocardial ischemia, which was not revealed by pathological examination. The underestimated non-TM segments located adjacent to the intact segments or opposite to the severely ischemic segments. From the echocardiographic viewpoint, nearly 90% of segments showing akinetic or dyskinetic motion had MI. However, one third of segments diagnosed as normal were actually MI segments.

Aged↗
PubMed1984

Echocardiographic features of bioprosthetic valve endocarditis.

Abnormal echocardiographic findings in seven cases of bioprosthetic valve endocarditis were confirmed in six at operation. The echocardiograms showed three cases with thickening and increased echo intensity (group 1) and four (group 2) in which vegetations were seen initially without either of the two features in group 1. Two patients in group 1 had vegetations, the causative organism being a streptococcus. Staphylococcus epidermidis was the causative organism in three of the four cases in group 2; in two of these rapidly growing vegetations were detected. The large vegetations obstructed the ostium of the bioprosthetic valve. Thus if vegetations are detected in cases in which staphylococci are the causative bacteria surgery should be performed as soon as possible. In patients who develop a fever after bioprosthetic valve replacement and especially in those with evident bacteraemia echocardiography should be repeated frequently so that lesions may be detected early.

Adult↗
PubMed1984

Mitral valve abnormalities in patients with right ventricular pressure overload. Analysis by real time cross sectional echocardiography.

Abnormalities of the mitral valve in patients with pulmonary stenosis, tetralogy of Fallot, and pulmonary hypertension with right ventricular pressure overload were studied by real time cross sectional echocardiography. Dislocation of the anterior and posterior mitral leaflets at the coaptation zone in systole was present in 16 of 46 cases: nine of 11 (82%) cases of pulmonary hypertension, four of 20 (20%) cases of tetralogy of Fallot, and three of 15 (20%) cases of pulmonary stenosis. The incidence was highest in patients with pulmonary hypertension. In eight of the 16 patients with mitral valve lesions, mitral regurgitation was seen on left ventriculograms or cross sectional Doppler echocardiograms. The dislocation was located near the posteromedial commissure of the anterior mitral leaflet in all cases. These findings are similar to the mitral valve abnormalities seen in patients with secundum atrial septal defect, and therefore may be due to a common cause. No relation could be found between the left ventricular deformity index and the incidence of dislocation of the mitral leaflets. Thus, the reason why this mitral valve abnormality occurs in conditions with right ventricular pressure overload could not be established.

Adolescent↗
PubMed1984

Clinical features of intracardiac thrombosis based on echocardiographic observation.

The nature of intracardiac thrombi were studied, which were the clinical underlying conditions, relation to systemic embolism, growth of thrombus and effect of anticoagulant therapy on the size of the thrombi, in 818 patients with mitral valve disease and 1000 patients with myocardial infarction by two-dimensional echocardiography. (1) Common underlying conditions were atrial fibrillation, enlarged left atrial cavity and predominance of mitral stenosis in cases with left atrial thrombi, and apical asynergy and low ejection fraction in cases with ventricular thrombi. The blood stasis should be the major factor in the formation of intracardiac thrombi. In a condition of blood stasis, dynamic intracavitary echoes which may represent erythrocyte aggregation were observed. (2) The incidence of systemic embolism in patients with thrombi was higher than that in patients without thrombi in cardiac disease. (3) The intracardiac thrombi were living. They grew and/or reduced their size spontaneously and sometimes became detached from the cardiac wall in the form of ball thrombi. (4) The effect of anticoagulant therapy on the regression of thrombi depends on its age.

Adult↗
PubMed1984

[Left ventricular thrombus formation and cuspal fusion of the prosthetic valve during left heart bypass: their pathophysiological significance and echocardiographic observations].

The echocardiographic findings during left ventricular assist of a heart of a 36-year-old woman who underwent mitral valve replacement were described. Blood was bypassed from the left atrium to the aorta. Echocardiography demonstrated that the pulmonary and tricuspid valves functioned with each heart beat, but that the aortic and prosthetic mitral valves did not open, and the left ventricular wall did not contract. In the left ventricular cavity, there was a mobile and amorphous thrombus which correlated with dynamic intracavitary micro-echoes ("moya moya" echoes). With higher left atrial pressure, the left ventricular motion increased slightly, and the left ventricular dimension gradually decreased. These findings were interpreted as follows: (1) desired results were attained from the previous powerful assist, or (2) the most optimum pressure of the left atrium in relation to the left ventricle was relatively high. It has not yet been determined which is actually the case. The "moya moya" and thrombus echoes were decreased. The general condition of the heart appeared to be improved, but the prosthetic valve motion was not observed. Contrast study via an echocardiographically-guided catheter inserted retrogradely into the left ventricular cavity revealed prosthetic valve stenosis. Fusion of its cusps by fibrin was confirmed on repeat surgery. Although the patient's condition allowed removal of the left ventricular assist device after surgery, the patient died of progressive infection. Optimum powerful assist should be performed while the formation of thrombi and cuspal adhesions is being prevented by other methods, or a more mild assist may be desirable.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1984

[Mitral valve lesions in patients with right ventricular pressure overload: analysis using realtime, two-dimensional echocardiography].

Mitral valve lesions in patients with right ventricular pressure overload, such as pulmonary stenosis, tetralogy of Fallot, and pulmonary hypertension, were studied by real-time, two-dimensional echocardiography, and the following results were obtained. The abnormality observed in the mitral valve was a systolic dislocation of the anterior and posterior mitral leaflets at the coaptation zone. Mitral valve lesions were noted in 16 of 46 cases, i.e. nine of 11 with pulmonary hypertension (82%), four of 20 with tetralogy of Fallot (20%), and three of 15 with pulmonary stenosis (20%). The incidence was highest in patients with pulmonary hypertension. In eight of 16 cases with mitral valve lesions, mitral regurgitation was observed by either left ventriculography or two-dimensional Doppler echocardiography. Mitral valve lesions were always located at the posteromedial commissure of the anterior mitral leaflet. Considering the previous similar reports in secundum atrial septal defect, we attributed the cause of the mitral valve lesions to the same mechanism. No clear relation could be found between the left ventricular deformity index and the incidence of mitral valve lesion. Therefore, we could not conclude about the mode of production of mitral valve lesions occurring in the diseases with right ventricular pressure overload.

Adolescent↗
PubMed1984

[Ventricular interdependence reflected in interventricular septal motion: with special reference to right ventricular pressure overload].

The dynamic features of the interventricular septum were studied with two-dimensional echocardiography with special reference to the influence of right ventricular (RV) pressure overload. The subjects were 52 patients, including 30 with atrial septal defect (ASD), 14 with rheumatic mitral valvular disease and 8 with pulmonary hypertension (PH) due to cor pulmonale, pulmonary embolism, or primary PH. To assess septal motion, the configuration of the left ventricle (LV) in the short-axis view was quantified as the deformity index, and characterized as the distortion from right circle. As an accurate short axis was required to assess the deformity of the cavity, the transducer was attached to the guide arm, providing comparable positions and directions. The deformity index was highest at the chordal level among other levels in the same cardiac phase. In ASD without PH, the deformity was minimal in end systole and maximal in early diastole. The index curve showed two peaks in early diastole and these times coincided with those of the minute backward notches on the ventricular septal echogram. In ASD with PH, the deformity was minimal in early systole and became greater during systole. The maximum deformity was shown in early diastole, corresponding to the momentary retracting motion of the septum by M-mode echocardiography. At that moment, the septum became convex to the LV. In patients with RV pressure overload, the systolic peak of the RV pressure was delayed and the decrease in pressure became sluggish, resulting in the RV pressure exceeding that of the LV transiently in early diastole. This was the reason for the septum becoming convex to the LV in this phase. Among the patients, the bi-ventricular systolic pressure ratio correlated not only with the index in end systole but also with that in early diastole. Good correlation between systolic pressure ratio and early diastolic deformity index seemed to be attributable to the fact that the higher the RV systolic pressure, the larger the reversed pressure gradient between both ventricles in early diastole.(ABSTRACT TRUNCATED AT 400 WORDS)

Diastole↗
PubMed1984

[Analysis of left ventricular blood flow in cases of myocardial infarction: a preliminary report].

Analysis of left ventricular blood flow in cases of myocardial infarction was attempted by two-dimensional Doppler echocardiography. Subjects consisted of 25 cases of myocardial infarction with and without ventricular aneurysm, and 15 healthy persons as controls. The Doppler recordings were made in nine areas within the left ventricular cavity from the apical approach. For healthy subjects, ejection flows were recorded in the main cavity and directed towards the aortic orifice in systole, and diastolic flows in the left ventricular inflow were recorded from the mitral orifice to the apex. However, diastolic flows toward the aortic orifice were also recorded along the interventricular septum, and interpreted as eddy currents from the apical cavity. There were no high velocity flows in the phases of isometric contraction and relaxation. In seven of 25 cases of myocardial infarction, abnormally high velocity flows of more than 30 cm/sec were recorded in the isometric relaxation phase, which were directed away from the asynergic part. In eight of the 25 patients examined, high velocity flows toward the cardiac apex were recorded at the posteroapical area in systole. Such flows have never been observed in healthy subjects. Inertia of the diastolic mitral inflow is considered to continue during systole due to impairment of contractions of the apicoinferior wall.

Adolescent↗
PubMed1983

Mitral valve lesion associated with secundum atrial septal defect. Analysis by real time two dimensional echocardiography.

Mitral valve lesions accompanying secundum atrial septal defect were examined in 120 successive patients from May 1978 to December 1980 using real time two dimensional echocardiography. The conclusions were as follows: (1) The characteristic feature of the mitral lesion accompanying secundum atrial septal defect is a dislocation of the mitral leaflet toward the left atrial side in the area of coaptation. (2) The mitral lesion is seen in about half the patients with secundum atrial septal defect. (3) It is usually seen only in the anterior leaflet, and is found near the posteromedial commissure. Lesions in other sites on the leaflet all accompany those near the posteromedial commissure. (4) The incidence, extent, and degree of the mitral valve lesion increase with age. (5) It is assumed that the mitral valve lesion in secundum atrial septal defect starts near the posteromedial commissure in the anterior leaflet, gradually deteriorates, and extends toward the anterolateral commissure. (6) It is probable that the mitral lesion results in mitral regurgitation. (7) The mitral valve lesion is similar in appearance to mitral valve prolapse caused by the floppy mitral valve, though their causative factors may be different. It is probably the reason why the mitral valve abnormality has been described as mitral valve prolapse in previous reports. In the present study the mitral lesion was evaluated on the distance of the dislocation between both leaflets at the area of coaptation. These criteria proved useful. Because of the similarity in appearance, it may be helpful in the assessment of primary mitral valve prolapse.

Adolescent↗